Male frog differs from the female frog in having

Options

A. Vocal sacs
B. Amplexusory pads
C. Both of these
D. None of these

Answer

### Step-by-Step Solution:

1. **Identify the Differences**: Male frogs differ from female frogs in several anatomical and physiological aspects.

2. **Nuptial Pads**: During the mating period, male frogs develop spiny nuptial pads on their forelimbs. These pads help them grip onto the female during mating.

3. **Vocal Sac**: Male frogs possess a vocal sac, which is a flexible membrane of skin. This structure is used to amplify their mating calls, which serve as an advertisement to attract female frogs.

4. **Narrow Abdomen**: Male frogs typically have a narrower abdomen compared to female frogs. This difference in body shape is another distinguishing characteristic.

5. **Summary of Features**: The key features that differentiate male frogs from female frogs are:
- Nuptial pads
- Vocal sac
- Narrow abdomen

6. **Conclusion**: Therefore, male frogs can be distinguished from female frogs by the presence of nuptial pads, vocal sacs, and their narrower abdomen.